Jeff. Miker's reference to John Mummert's web site should be helpful, IF the heads were not swapped over time.
Isn't it interesting that such different heads were used on the different makes of FoMoCo vehicles that year in spite of them all having y-blocks?!
Let me add to what JM's reference list for '59 engines shows . . .
292 Ford passenger cars with 292 engine . . . . . 5752-113 heads
292 Ford LD, MD, HD trucks with 292 engine . . . 5750-471 heads
312 Mercury with 312 engine . . . . . . . . . . . . . . 5750-471 heads
292 Edsel with 292 engine . . . . . . . . . . . . . . . . 5752-113 heads
Best Wishes on your hunt. Hope this helps!
NoShortcuts
a.k.a. Charlie Brown
near Syracuse, New York